Chandra Implicates Type 2 Quasars in the X-ray Background Mystery!

During the last few years deep sky surveys with Japan's Advanced Satellite for Cosmology and Astrophysics (ASCA) and the Italian-Dutch BeppoSAX X-ray satellite gave support to the
idea that more than Type 1 quasars are needed to produce the X-ray background glow. This research showed that about 30% of the X-ray background could be resolved into distinct sources.

With Chandra's great sensitivity and focusing ability, a team led by Richard Mushotzky of the NASA Goddard Space Flight Center reported that they were
able to resolve at least 75 percent of the X-ray background. Another team led by Gordon Garmire of Penn State University has reported similar
results.

2/3 of the ducks on the cosmic pond were missed by previous surveys.

About a third of the sources detected by Mushotzky's team were Type 1 quasars, that is, they showed no evidence of a dense blanketing cloud of gas and dust. The remaining two-thirds of the sources
appear to be veiled giant black holes.

Conclusion: The giant black hole population in the universe is 3 times as great as observations with optical telescopes indicate. It is as if previous bird counts had
missed two-thirds of the ducks because they didn't sound like ducks!

Episode 3
April 3, 2000 :: Many astronomers believe it is possible that type 2 quasars exist. Others maintain that they MUST exist in order to explain the mysterious X-ray background radiation. Episode 3